code: def test_trivial_hierarchy(self):
      trivial_hierarchical_map = {
          "Plant": {"Plant": ("Rose", "Daisy", "Daffodil", "Bluebell")}
      }
  
      enc_hier = encoders.TargetEncoder(
          verbose=1,
          smoothing=2,
          min_samples_leaf=2,
          hierarchy=trivial_hierarchical_map,
          cols=["Plant"],
      )
      result_hier = enc_hier.fit_transform(
          self.hierarchical_cat_example,
          self.hierarchical_cat_example["target"],
      )
      enc_no_hier = encoders.TargetEncoder(
          verbose=1, smoothing=2, min_samples_leaf=2, cols=["Plant"]
      )
      result_no_hier = enc_no_hier.fit_transform(
          self.hierarchical_cat_example,
          self.hierarchical_cat_example["target"],
      )
      pd.testing.assert_series_equal(
          result_hier["Plant"], result_no_hier["Plant"]
      )
  
imports: import pandas
  from unittest import TestCase
  import tests.helpers
  import numpy
  from category_encoders.datasets import load_postcodes, load_compass
  import category_encoders
label_desc: Use image node_id 16 for calling the TestTargetEncoder obj's underlying member method code with example usage: obj.test_trivial_hierarchy() without return types